1. Field of the Invention
The present invention relates to a vibration motor, and more particularly, to a vibration motor capable of increasing coupling force between a housing and a cover.
2. Description of the Related Art
Generally, a vibration motor has a structure in which a rotor having an eccentric mass with respect to a shaft rotates to produce mechanical vibrations. Here, the rotor rotates by receiving current in a coil thereof through contact between a brush and a commutator.
However, a vibration motor using a brush and a commutator has disadvantages, in that mechanical friction between the brush and the commutator may be high, and electrical sparks may be generated through contact between the brush and the commutator, such that a lifespan of the motor may be shortened.
In addition, a vibration motor having this type of structure is inappropriate for use in an output device requiring a rapid response since it may take a certain amount of time to reach a target oscillation frequency.
As a motor for overcoming these disadvantages, there is provided a linear vibration motor.
The linear vibration motor may allow a mass member fixed to an elastic member, vibrated through electromagnetic force, to relatively rapidly generate a oscillation frequency desired by a user.
The linear vibration motor has a structure in which a housing and a cover are coupled to each other by welding. However, this coupling structure may be disadvantageous, in that a molten material may penetrate into the housing to change vibration characteristics of the linear vibration motor (for example, generate noise therein).